hello-algo/codes/go/chapter_graph/graph_adjacency_matrix.go
Reanon 93ca29ca6d
feat(graph): add go codes (#314)
* feat(graph): add go codes

* feat(go/graph): add graph_adjacency_list

* doc(graph): add go codes

* fix(graph): fix go codes

* Update graph_adjacency_matrix_test.go

---------

Co-authored-by: Yudong Jin <krahets@163.com>
2023-02-05 16:08:08 +08:00

101 lines
2.6 KiB
Go
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

// File: graph_adjacency_matrix.go
// Created Time: 2023-01-31
// Author: Reanon (793584285@qq.com)
package chapter_graph
import "fmt"
/* 基于邻接矩阵实现的无向图类 */
type graphAdjMat struct {
// 顶点列表,元素代表“顶点值”,索引代表“顶点索引”
vertices []int
// 邻接矩阵,行列索引对应“顶点索引”
adjMat [][]int
}
func newGraphAdjMat(vertices []int, edges [][]int) *graphAdjMat {
// 添加顶点
n := len(vertices)
adjMat := make([][]int, n)
for i := range adjMat {
adjMat[i] = make([]int, n)
}
// 初始化图
g := &graphAdjMat{
vertices: vertices,
adjMat: adjMat,
}
// 添加边
// 请注意edges 元素代表顶点索引,即对应 vertices 元素索引
for i := range edges {
g.addEdge(edges[i][0], edges[i][1])
}
return g
}
/* 获取顶点数量 */
func (g *graphAdjMat) size() int {
return len(g.vertices)
}
/* 添加顶点 */
func (g *graphAdjMat) addVertex(val int) {
n := g.size()
// 向顶点列表中添加新顶点的值
g.vertices = append(g.vertices, val)
// 在邻接矩阵中添加一行
newRow := make([]int, n)
g.adjMat = append(g.adjMat, newRow)
// 在邻接矩阵中添加一列
for i := range g.adjMat {
g.adjMat[i] = append(g.adjMat[i], 0)
}
}
/* 删除顶点 */
func (g *graphAdjMat) removeVertex(index int) {
if index >= g.size() {
return
}
// 在顶点列表中移除索引 index 的顶点
g.vertices = append(g.vertices[:index], g.vertices[index+1:]...)
// 在邻接矩阵中删除索引 index 的行
g.adjMat = append(g.adjMat[:index], g.adjMat[index+1:]...)
// 在邻接矩阵中删除索引 index 的列
for i := range g.adjMat {
g.adjMat[i] = append(g.adjMat[i][:index], g.adjMat[i][index+1:]...)
}
}
/* 添加边 */
// 参数 i, j 对应 vertices 元素索引
func (g *graphAdjMat) addEdge(i, j int) {
// 索引越界与相等处理
if i < 0 || j < 0 || i >= g.size() || j >= g.size() || i == j {
fmt.Errorf("%s", "Index Out Of Bounds Exception")
}
// 在无向图中,邻接矩阵沿主对角线对称,即满足 (i, j) == (j, i)
g.adjMat[i][j] = 1
g.adjMat[j][i] = 1
}
/* 删除边 */
// 参数 i, j 对应 vertices 元素索引
func (g *graphAdjMat) removeEdge(i, j int) {
// 索引越界与相等处理
if i < 0 || j < 0 || i >= g.size() || j >= g.size() || i == j {
fmt.Errorf("%s", "Index Out Of Bounds Exception")
}
g.adjMat[i][j] = 0
g.adjMat[j][i] = 0
}
/* 打印邻接矩阵 */
func (g *graphAdjMat) print() {
fmt.Printf("\t顶点列表 = %v\n", g.vertices)
fmt.Printf("\t邻接矩阵 = \n")
for i := range g.adjMat {
fmt.Printf("\t\t\t%v\n", g.adjMat[i])
}
}